Device for delivering fuel from a tank to an internal combustion engine

ABSTRACT

A device for delivering fuel having a delivery unit, a main filter with a filter housing situated downstream of the delivery unit, and a drive line for driving a suction jet pump embodied in the filter housing of the main filter. As a result, the assembly and manufacture costs of the device are reduced.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a 35 USC 371 application of PCT/EP 2005/051937 filedon Apr. 28, 2005.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention is directed to an improved device for delivering fuel toan internal combustion engine.

2. Brief Description of the Prior Art

A device for delivering fuel known from EP 0 959 242 B1 has a deliveryunit, a main filter with a filter housing situated downstream of thedelivery unit, and a drive line for driving a suction jet pump. It isdisadvantageous that the drive line must be installed in the device as aseparate part. As a result, the assembly and manufacture costs of thedevice are comparatively high.

SUMMARY AND ADVANTAGES OF THE INVENTION

The device according to the invention has the advantage over the priorart that manufacturing costs can be reduced in a simple manner due tothe fact that the drive line is provided in the filter housing of themain filter. The drive line is integrated into the filter housing sothat it is no longer necessary to mount any additional, separate supplylines to the suction jet pump.

According to an advantageous embodiment, the filter housing has a filterbowl and a filter lid that closes the filter bowl; the drive line isembodied in the filter bowl and/or in the filter lid.

It is particularly advantageous if the filter bowl has a first shoulderon its end oriented toward the filter lid and the filter lid has asecond shoulder on its side oriented toward the filter bowl; the firstshoulder and the second shoulder rest against each other in flangefashion. In this manner, the drive line can be integrated into theflange constituted by the first shoulder and the second shoulder.

It is very advantageous if a first segment of the drive line is providedin the first shoulder of the filter bowl and/or in the second shoulderof the filter lid since in this way, a segment of the drive line isprovided between the filter bowl and the filter lid and is formed andsealed when the filter bowl and filter lid are joined to each other.

It is also advantageous if a pressure line is provided, leading from thedelivery unit via a check valve to the internal combustion engine, thefirst segment being connected to the pressure line upstream of the checkvalve. According to this advantageous embodiment, the drive line isequipped with a throttle element and/or an additional prefilter. Thethrottle element serves to limit the volumetric flow traveling throughthe suction jet pump. Since the fuel of the drive line was divertedupstream of the main filter and has therefore not yet been finelyfiltered, the additional prefilter prevents clogging of the throttleelement and/or the suction jet pump nozzle.

It is also advantageous if a second segment of the drive line isprovided in the filter bowl, extending from the first shoulder of thefilter bowl in the direction of a bowl bottom of the filter bowl, sincethis embodiment allows the filter bowl to be easily manufactured bymeans of injection molding technique and facilitates its demolding.

It is also advantageous if the filter lid is equipped with an additionalsegment of the drive line, which leads from a pressure control valvesituated downstream of the main filter and is connected to the secondsegment of the drive line; the first segment of the drive line is sealedoff from the second segment by means of a bulkhead. This embodimentmakes it possible to change the flow routing in the device in a simplemanner by exchanging the filter lid and by providing a bulkhead in thefirst segment of the drive line. Depending on the choice of the filterlid, it is consequently possible to connect the suction jet pumpdirectly to the pressure line upstream of the main filter or to connectit indirectly via a pressure control valve to the pressure linedownstream of the main filter. In this manner, the so-called modularprinciple is used, which permits various embodiments of the device withas many shared components as possible.

It is also advantageous if the delivery unit has an outlet fitting thatprotrudes into a filter inlet of the filter housing since thiseliminates the need for a separate tube leading from the delivery unitto the filter housing.

It is also advantageous if the filter inlet is flow-connected to thedrive line via an opening.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the invention will be explained in detail inthe subsequent description, taken in conjunction with the drawings, inwhich:

FIG. 1 schematically depicts a device for delivering fuel according to afirst embodiment of the invention,

FIG. 2 schematically depicts a device for delivering fuel according to asecond embodiment,

FIGS. 3 and 4 depict a device for delivering fuel according to the firstembodiment, and

FIG. 5 depicts a device for delivering fuel according to the secondembodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The device shown is used, for example, to deliver fuel from a tank 1into a collecting receptacle 2 and from there, via a delivery unit 3 toan internal combustion engine 4 of a motor vehicle.

The collecting receptacle 2 is contained inside the tank 1 and thedelivery unit 3 is contained inside the collecting receptacle 2. Forexample, the delivery unit 3 is a dynamic pump or a displacement pump.

The for example bowl-shaped collecting receptacle 2 stores enough fuelto assure a supply of fuel to the internal combustion engine 4 via thedelivery unit 3, even when no fuel is being fed into the collectingreceptacle 2, for example during cornering and the accompanying sloshingmovements of fuel in the tank 1.

The delivery unit 3 draws fuel from the collecting receptacle 2, forexample via a prefilter 5 and an intake line 6, and supplies the fuelvia an outlet fitting 7 to a pressure line 8 that leads to the internalcombustion engine 4. The prefilter 5 protects the device downstream ofthe prefilter 5 from coarse dirt particles contained in the fuel.

The pressure line 8 contains a check valve 9 and, downstream of thecheck valve 9, a main filter 10. When the delivery unit 3 is switchedoff, the check valve 9 prevents fuel from flowing out of the pressureline 8 downstream check valve 9 to the upstream side of the check valve9, through the delivery unit 3, the intake line 6, and the prefilter 5,back into the collecting receptacle 2. The main filter 10 filters outfine dirt particles contained in the fuel, thus protecting, for example,the injection valves of the internal combustion engine from becomingclogged.

Downstream of the main filter 10, a pressure relief line 13 containing apressure control valve 14 branches off from the pressure line 8. If thepressure in the pressure line 8 exceeds a predetermined value, thepressure control valve 14 opens and allows fuel to flow out of thepressure line 8 via the pressure relief line 13 and back into thecollecting receptacle 2. In this way, the pressure in the pressure line8 falls back below the predetermined pressure and the pressure controlvalve 14 closes again.

Downstream of the delivery unit 3 and upstream of the check valve 9 ofthe embodiment of FIG. 1, a drive line 15 branches off from the pressureline 8; this drive line 15 serves to supply fuel from the pressure line8 to a so-called suction jet pump 16 in order to drive it. In order toprevent the delivery unit 3 from emptying the collecting receptacle 2,the suction jet pump 16 feeds fuel from the tank 1 via a flow connectioninto the collecting receptacle 2, for example via a bottom valve 17 andan intake line 18. The aspirated fuel is supplied together with theso-called motive jet of the drive line 15 into the collecting receptacle2. A throttle element 21 is provided in the drive line 15 in order toset and limit the volumetric flow traveling via the drive line 15. Inorder to prevent the throttle element 21 from becoming clogged, andadditional prefilter 22 is provided in the drive line 15, upstream ofthe throttle element 21.

A suction jet pump is known, for example, from DE 198 56 298 C1, whosecontent is expressly intended to constitute part of the disclosure ofthe present application.

In the device according to FIG. 2, parts that are the same or functionin the same manner as those in the device according to FIG. 1 have beenprovided with the same reference numerals.

The device according to FIG. 2 differs from the device according to FIG.1 in that the drive line 15 branches off from the pressure line 8downstream of the main filter 10. In the embodiment according to FIG. 2,the pressure relief line 13 from the embodiment according to FIG. 1 isreplaced, downstream of the pressure control valve 14, by the drive line15 in which the pressure relief valve 14 is provided.

The additional prefilter 22 according to the first embodiment iseliminated because the fuel downstream of the main filter 10 has alreadybeen filter by the main filter 10. Since the pressure control valve 14limits the volumetric flow of the drive line 15, the throttle element 21can be eliminated in the second embodiment.

FIG. 3 shows a section through the fuel delivery device according to theinvention in the embodiment according to FIG. 1.

In the device according to FIG. 3, parts that are the same or functionsin the same manner as those in the device according to FIG. 1 and FIG. 2have been provided with the same reference numerals.

The delivery unit 3 is contained in a bracket 25 in the collectingreceptacle 2.

The main filter 10 contained in the collecting receptacle 2 is providedin a filter housing 26 having, for example, a filter bowl 27 with a boldbottom 31 and having a filter lid 28 that closes the filter bowl 27. Forexample, the filter housing 26 is situated next to the delivery unit 3.

With the outlet fitting 7, for example, the delivery unit 3 reaches intoa filter inlet 24 of the filter housing 26. The fuel exits the deliveryunit 3 via the outlet fitting 7, traveling into the filter inlet 24,which is part of the pressure line 8 and is sealed off from thecollecting receptacle 2. The pressure line 8 between the outlet fitting7 and the check valve 9 contains a branch point 36 equipped with a firstflow path a and a second flow path b. The branch point 36 is situated,for example, in the filter inlet 24 and leads along a flow path a viathe check valve 9 into a filter chamber 32 of the filter housing 26. Inthe first embodiment according to FIG. 1, the flow path b of the branchpoint 36 is flow connected to the drive line 15 via an opening 38. Theopening 38 is provided in the filter bowl 27 and/or in the filter lid28.

The check valve 9 is situated in the filter housing 26, for examplebetween the filter lid 28 and the end of the filter bowl 27 orientedtoward from the filter lid 28, in a recess 35 of the filter housing 26that is flow-connected to the filter inlet 24.

The filter chamber 32 contains the main filter 10 through which the fuelflows, for example, from the radial outside to the radial inside inrelation to a filter axis 29. The fuel exits the filter chamber 32 atthe downstream end via a filter outlet 30 in the direction of theinternal combustion engine 4. The filter outlet 30 is embodied in theform of a fitting and is provided, for example, on the filter lid 28.The fitting of the filter outlet 30 is provided, for example, with avalve connection 33 for the pressure control valve 14 and an outletfitting 34 for connection to the internal combustion engine 4. Forexample, this results in a T-shaped branch point, the one branch leadingto the pressure control valve 14 and the other branch leading to theinternal combustion engine 4. The pressure control valve 14 is mountedonto the valve connection 33, e.g. is clipped, screwed, plugged, orwelded onto it.

According to the invention, the drive line 15 is embodied in the filterhousing 26 of the main filter 10, for example in the filter bowl 27and/or the filter lid 28, and is produced so that it is integral to thiscomponent or components at the time of manufacture. The drive line 15 isintegrated into the filter housing 26 so that few or no separate flowlines are required.

According to a first exemplary embodiment, the drive line 15 extends ina for example semi-annular first segment 37 in the circumferentialdirection and in a second segment 42, extends in the axial directionwith regard to the filter axis 29. The first segment 37 and the secondsegment 42 are provided, for example, on the outer circumference of thefilter housing 26.

In terms of its flow cross section, the first segment 37 of the driveline 15 is situated, for example, partially in the filter bowl 27 andpartially in the filter lid 28; a closed conduit is produced after thefilter bowl 27 and the filter lid 28 are joined to each other. Forexample, one half of the flow cross section of the first segment 37 isprovided in the filter bowl 27 and the other half is provided in thefilter lid 28. The first segment 37 can, however, also be embodied sothat the flow conduit of the first segment 37 is provided entirely inthe filter bowl 27, but is open on the side oriented toward the filterlid 28 so that the filter lid 28 tightly seals the flow conduit on theopen side. Likewise, the first segment 37 can also be embodied so thatthe flow conduit of the first segment 37 is completely contained in thefilter lid 28, but is open on the side oriented toward the filter bowl37 so that the filter bowl 27 tightly seals the flow conduit on the openside.

The filter bowl 27 and the filter lid 28 are attached to each other, forexample, by being glued, welded, clipped, screwed, or joined in someother way.

The filter bowl 27 and the filter lid 28 are embodied, for example, inflange fashion at a joining surface 39, the filter bowl 27 having afirst shoulder 40 on its end oriented toward the filter lid 28 and thefilter lid 28 having a second shoulder 41 oriented toward the filterbowl 27. After the filter bowl 27 is joined to the filter lid 28, thefirst shoulder 40 and the second shoulder 41 rest snugly against eachother.

The first shoulder 40 and the second shoulder 41 extend, for example, inthe circumferential direction in relation to the filter axis 29 over atleast part of the circumference of the filter housing 26. The shoulders40, 41 are therefore at least semi-annular in shape; in the region ofthe filter inlet 24, they extend, for example, around the outlet fitting7 of the delivery unit 3 and the filter inlet 24 and constitute a secondpartial ring.

The first segment 37 of the drive line 15 is embodied, for example, inthe first shoulder 40 and/or in the second shoulder 41.

For example, the flow cross section of the first segment 37 of the driveline 15 is square, rectangular, polygonal, circular, or oval.

The second segment 42 of the drive line 15 that is flow-connected to thefirst segment 37 is embodied, for example, only in the filter bowl 27and extends from the first shoulder 40 in a straight line, for example,and transversely in relation to the first segment 37, in the directionof the bowl bottom 31.

In the vicinity of the transition to the second segment 42 of the driveline 15, the second shoulder 41 of the filter lid 28 has a bulge 43, forexample, that is oriented radially outward, overlaps the end of thesecond segment 42 of the drive line 15 oriented toward the filter lid28, and seals it tightly. The shape and size of the bulge 43 is adaptedto the shape of the second segment 42 of the drive line 15.

The flow cross section of the second segment 42 of the drive line 15 isembodied, for example, as circular, but can also be square, rectangular,polygonal, or oval.

For example, the additional prefilter 22 is provided in the secondsegment 42 of the drive line 15, for example at the end oriented towardthe first segment 37, and the throttle element 21 is situated downstreamof the additional prefilter 22. For example, the additional prefilter 22and the throttle element 21 are integrally connected to each other. Theend of the second segment 42 of the drive line 15 oriented toward thebowl bottom 31 is tightly connected to the inlet connection 45 of thesuction jet pump 16.

The suction jet pump 16 is situated, for example, on a bottom 44 of thecollecting receptacle 2, draws fuel from the tank 1 and supplies it,along with the fuel of the drive line 15, into the collecting receptacle2 via a mixing conduit 46.

FIG. 4 shows a second section through the fuel delivery device accordingto the invention in the embodiment according to FIG. 1.

In the device according to FIG. 4, parts that are the same or functionin the same manner as those in the device according to FIGS. 1 through 3have been provided with the same reference numerals.

FIG. 4 shows the annular course of the first segment 37 of the driveline 15.

FIG. 5 shows a section through the fuel delivery device according to theinvention in the embodiment according to FIG. 2.

In the device according to FIG. 5, parts that are the same or functionin the same manner as those in the device according to FIGS. 1 through 4have been provided with the same reference numerals.

The device according to FIG. 5 differs from the device according to FIG.3 and FIG. 4 in that the drive line 15 branches from the pressure line 8downstream of the main filter 10; the pressure relief valve 14 permitsfuel to flow into the drive line 15 as soon as the pressure in thepressure line 8 exceeds a predetermined value.

As a result of the altered flow routing, in the second exemplaryembodiment, a filter lid 28 is used that is different from the one inthe first embodiment according to FIG. 3 and FIG. 4, but for example thesame filter bowl 27 is used as in FIG. 3 and FIG. 4. This corresponds tothe use of the so-called modular principle, in which as many sharedcomponents as possible are used for different embodiments.

According to the invention, the different flow routing according to FIG.5 is achieved essentially by replacing the filter lid 28, but it is alsopossible for additional and/or other parts to be different, too.

In the second embodiment, in order to prevent fuel from being able toflow via the first segment 37 directly into the second segment 42 of thedrive line 15, in the embodiment according to FIG. 5, for example, theopening 38 is closed in relation to the drive line 15 or the firstsegment 37 of the drive line 15 is tightly sealed off from the secondsegment 42 of the drive line 15 by means of a bulkhead 47 situated inthe first segment 37.

According to the second embodiment, at the filter outlet 30 of thefilter lid 28, in addition to the connection fitting—not shown in FIG.5—for connecting to the internal combustion engine 4, there is also apressure control valve 14, for example a diaphragm pressure regulator.The pressure of the filter outlet 30 acts via a valve inlet 48 on avalve-closure member, for example a diaphragm, of the pressure controlvalve 14. If the pressure in the filter outlet 30 exceeds apredetermined value, the pressure control valve 14 opens and allows fuelto flow out of the filter outlet 30, through the valve inlet 48 and avalve seat that is not shown, into an additional segment 50 of the driveline 13, 15.

The additional segment 50 of the drive line 13, 15 extends, for exampleleading from the valve seat cooperating with the valve-closure member,outward radially in relation to the filter axis 29, for example in astraight line. After a bend 52 in the additional segment 50, for exampleof 90°, the additional segment 50 extends in the axial direction and hasa bulge 43 situated at its end oriented toward the filter bowl 27. Thebulge 43 of the filter lid 28, which seals the end of the second segment42 according to the first embodiment in FIGS. 3 and 4, is connected,according to the second embodiment in FIG. 5, to the second segment 42of the drive line 15 via a connecting opening 51. The additional segment50 of the drive line 15 is situated, for example, so that downstream ofthe bend 52, it is aligned with the second segment of the drive line 15.

Depending on whether the filter lid 28 according to the first embodimentin FIGS. 3 and 4 or the filter lid 28 according to the second embodimentin FIG. 5 is used, a different flow routing to the suction jet pump 16is produced in the device; however, no separate lines, for example hosesor corrugated pipes, are required between the delivery unit 3 and thefilter outlet 30 and between the pressure line 8 and the suction jetpump 16. This simplifies assembly to a considerable degree andsignificantly reduces assembly and manufacture costs.

The embodiment of the drive line 15 in the filter housing 26 is thusadvantageous because the drive line 15 according to the first embodimentbranches off upstream of the filter housing 26 and according to thesecond embodiment, branches off downstream of the filter housing 26. Inorder to make use of the modular principle, therefore, the branch pointof the drive line 15 from the pressure line 8 to the suction jet pump 16is provided in the filter bowl 27 according to the first embodiment andis provided in the filter lid 28 according to the second embodiment.Both embodiments use the second segment 42 of the drive line 15 in thefilter bowl 27. In the second embodiment, the first segment 37 of thedrive line 15 is sealed off by the bulkhead 47 and is therefore unused.Instead of flowing into the second segment 42 of the drive line 15 viathe first segment 37, the fuel flows into it via the additional segment50.

The foregoing relates to a preferred exemplary embodiment of theinvention, it being understood that other variants and embodimentsthereof are possible within the spirit and scope of the invention, thelatter being defined by the appended claims.

1. In a device for delivering fuel from a tank to an internal combustionengine, having a delivery unit, a main filter in a filter housingsituated downstream of the delivery unit, and a drive line for driving asuction jet pump, wherein the drive line is embodied in the filterhousing of the main filter, wherein the filter housing comprises afilter bowl and a filter lid that closes the filter bowl, wherein thefilter bowl and the filter lid have a common joining surface, andwherein the drive line is embodied at the joining surface in the filterbowl and/or the filter lid.
 2. The device according to claim 1, whereinthe delivery unit comprises an outlet fitting that protrudes into afilter inlet of the filter housing.
 3. The device according to claim 2,wherein the filter inlet is flow-connected to the drive line via anopening.
 4. In a device for delivering fuel from a tank to an internalcombustion engine, having a delivery unit, a main filter in a filterhousing situated downstream of the delivery unit, and a drive line fordriving a suction jet pump, wherein the drive line is embodied in thefilter housing of the main filter, wherein the filter housing comprisesa filter bowl and a filter lid that closes the filter bowl, and whereinthe drive line is embodied in the filter bowl and/or the filter lid,wherein the filter bowl comprises a first shoulder on its end orientedtoward the filter lid and the filter lid corn rises a second shoulder onits side oriented toward the filter bowl, and wherein the first shoulderand the second shoulder rest against each other in flange fashion, andwherein a first segment of the drive line is provided in the firstshoulder of the filter bowl and/or in the second shoulder of the filterlid.
 5. The device according to claim 4, further comprising a pressureline which leads from the delivery unit via a check valve to theinternal combustion engine, the first segment being connected to thepressure line upstream of the check valve.
 6. The device according toclaim 5, wherein the drive line comprises a throttle element and/or anadditional prefilter.
 7. The device according to claim 4, wherein asecond segment of the drive line is provided in the filter bowl, thesecond segment extending from the first shoulder of the filter bowl inthe direction of a bowl bottom of the filter bowl.
 8. The deviceaccording to claim 7, wherein the filter lid comprises a pressurecontrol valve downstream of the main filter, an additional segment ofthe drive line which leads from the pressure control valve and isconnected to the second segment of the drive line, and a bulkheadsealing off the first segment of the drive line from the second segment.